I have heard that the rudder trim was found set hard left, FWIW.

You mean like how it say's in the Before Takeoff Checklist?

It would explain why the aircraft ended up taking out runway lights before even making it airborne. Doesn't explain why there wasn't an abort.

" That examination found that the cores of both engines were rotating and that there was no evidence of pre-impact failure of either engine’s internal components."

Junior. Rotating and producing power are 2 different things.

There was a 310 out of Tamworth in 2005 that got airborne and rolled over on its back with an obvious outcome. It took the ATSB a while to work that out but eventually they come to the conclusion that it had come out of the hangar with the rudder trim set full left. The pilot was to ferry it to Scone and was in a rush so missed the trim part of the checklist. If the trim on the Kingair was full left then it would go a long way to explain the flight path. If the pilot thought he had suffered an engine failure but the engines were producing power then there is too little time available to do any trouble shooting.

The problem for an investigation, if it is an incorrect trim setting, is that often the evidence can be destroyed in the crash.

Lookleft, the Tamworth accident has stayed with me. I knew the pilot and was one of the witnesses interviewed by the ATSB in that report.

While it is a great report I have always had lingering doubts about the findings which have not always sat well with me. There is an element to accidents where we may not always conclusively know everything after the event.

For example: "During the on-site examination of the wreckage, investigators located a number of tools including a damaged hand tool (Figure 6) that would not normally be expected to be carried on the aircraft."

...and: "The location of the bent hand tool in the wreckage raised the possibility that it may have contributed to the flight control difficulty. Despite the tool being found in the wreckage, it was not possible to establish whether it was in an internal section of the aircraft that contained part of a primary flight control system or when it had been introduced.
The bending damage to the tool was found to be consistent with severe impact and breakup forces and there was no evidence that the tool had interfered pre-impact with a control system. Such evidence, however, may not have been detectable post-accident."

The report investigates a number of possible probable causes, control interference, trim runaway, autopilot problem, and trim settings. In this case they concluded the report with what they believed to be a 'most probable' cause although other factors certainly cannot be ruled out:

"The limited evidence did not allow the investigation to be certain about the existence of abnormal rudder and/or aileron trim settings during the flight. However, in the absence of any other likely factor and with supporting evidence, the investigation considered that the pilot probably took off with abnormal rudder and/or aileron trim settings and with increasing airspeed, was unable to maintain control."

Flying over the smoking hole in the ground, attending the funeral of a talented young man with his devastated young bride dressed in black, grieving with the family over a life cut all too short (he wasn't even supposed to have been flying that day) stays in ones memory... RIP Jason C.

Be ever vigilant out there folks...

I know what you felt and continue to feel about losing a colleague and friend CN. My first attendance at a pilot's funeral was at age 24 and that is a long time ago. There were quite a few after that. Never gets easy. No report is easy to read when it involves someone you know.

We have probably met, Nomad. I too knew the young bloke and there are still whispers around Tamworth about the 'real' cause.

ATSB website lists the report release date as 24 Sep 2018 (this coming Monday)?

I have also heard the rumours that the rudder trim was found fully hard over to the left. It may have been but who knows if it was that way prior to impact. I very much doubt the rudder trim theory. From my experience I would suspect that the aircraft is almost impossible to keep straight and would very quickly veer off the runway resulting in an abort. I have experienced the friction nut scenario in the aircraft during an early morning take off and it definitely gets your attention. I have run the Essendon loose friction nut scenario in the Sim and ended up very close to the same spot as old mate.

Groggy

ATSB is handing down its report...not good for pic. Rudder trim and takeoff weight.

Exceeded MTOW??

With 5 POB on a day trip (so I would suspect limited luggage)....it begs the question - what the hell else was on board??

Oh dear. No doubt the regulator will emerge spotless and the people blamed will all be unable to answer for themselves.

Synopsis of the ATSB report:



https://www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-024/

I didn't see all the ATSB presentation....thanks ABC for switching away.
Was the question asked as to why the rudder trim was in the full left position?
Had the aircraft had any recent maintenance done that would have involved the rudder trim mechanism ?

If it was just rudder trim, why did the report take nearly 2 years?

From my initial scan of the report:

As i understand it, the PIC was the last person to fly the aircraft. So, who moved the trim?

The report infers that the pilot did not undertake a proper pre-flight, but despite CCTV footage is unable to provide any factual evidence - only speculation.

It notes that the preflight checks have 5 separate checks of the rudder trim, but has nothing other than speculation that says these were not conducted.

Examination of the wreckage clearly shows full LH rudder trim, but the report is mute on when or how it got that way.

ATSB say that based on ITS OWN estimation that the aircraft was 240kg over weight out of a total of 5670kg - or 4%. It also says that the CofG limits were within the fore / aft limits. this equates to 48 USG of the fuel capacity of 549 USG. I'd say that the ATSB is being too cute and that the 240kg it alleges that the aircraft was overweight was within the area of uncertainty of their estimation.

I think the B200 is an FAR 25 type certificate? Does anyone know if the type certificate requires demonstration that the aircraft is controllable with full rudder trim?

When the Partenavia that crashed at Essendon in the 1970's and it was found that the aircraft was not controllable at full elevator trim, an emergency AD was issued requiring the elevator trim to be limited. If the B200 is not controllable with full rudder trim, should there be a recommendation from the ATSB about an AD for B200 aircraft to limit rudder trim?

It hit the edge of the building, and ended up in the rear car park. Beyond that car park in the direction of flight is the freeway.

Weren't the Americans on a golfing holiday and planning to play a game at King Island? So they would have had golf clubs, which probably weigh 10-15kg a bag, maybe more. Don't know, I don't play. And given that fuel is likely quite expensive on the island, the fuel plan would have involved tankering. And what were they carrying as an alternate, DPO? Another 250km away...

Thanks for the additional info.

I have to say, I am extremely surprised that full mains, 400 litres in the auxers, five adults, and possibly four golf bags, puts the aircraft at an estimated 240kgs overweight.

I have no experience at all on the B200, but I assumed, naively, that they would have more payload than that.

The ATSB report says that the B200 is controllable with full left trim up to 140 KTAS (p46)
The ground speed data shows that the aircraft took off at 11 kt GS and peaked at approx 116 kt before decaying to approx 108 kts at impact (p28)
actual MET data recorded at 1 sec intervals shows the wind at 322 deg magnetic at 4-5 kts for a tailwind component of approx 4 kts
Therefore TAS of the aircraft is (approx) 107 kt (rotation) 112 kt (initial climb) 104 kt (impact).

So... why was the pilot not able to maintain directional control? The ATSB flight simulator exercise shows that at these speeds directional control could be maintained.

Also, why was the aircraft not CLIMBING? If the engines were producing full power, it should have either been diving (increasing airspeed) or climbing. Yet, its airspeed was decaying and it was not climbing.

the ATSB explanation that the cause was sideslip is flawed. The flight simulator testing (p46) was " in order to determine the effects of full left rudder trim on take-off and climb performance" and yet, the ATSB presents no data on take-off or climb performance from the simulator tests and goes on to say " "it was not possible to quantify the effects on ZCR without flight testing or complex engineering modelling. Both of these options was outside the scope of investigation...". This is the very core of the issue that the ATSB conclude, but they say its outside the scope of the investigation????? Really??

The ATSB has labelled the cause as full left rudder trim, yet has not put forward an explanation how it occurred, or how a pilot with 2400 hours on B200 all of a sudden forgot. Nor has the ATSB made any real attempt to prove its theory that the rudder trim led to yaw which led to lack of climb performance. The simulator work that the ATSB commissioned demonstrated that the aircraft could maintain directional control by the pilot at the airspeeds recorded by VH-ZCR. So why didn't a very experienced B200 pilot not push harder on the rudder, keep the aircraft straight and fly away?

It's 40 mins each way, so would hardly need a refill. Unless the plan was to fly somewhere else before returning to Essendon?

While the report tells us what caused the accident, there are certainly many unanswered questions.

It was 4% overweight by the ATSB's estimation - for which they have presented no details.

the PIC was reasonably light. Lets call the passengers 100 kg ea with 30 kg of bags each. This should still leave over 1300kg for fuel. Google tells me a bit over 100 gph in the cruise = about 320kg/hr = 4 hours range. Even with the new CASA fuel reserves that seems a lot for King Is & back.

Bingo. Checked the full travel of the trim tab in the pre flight combined with Old mate's propensity to wing the checklists and she's heading for the shops....

Well so much for the PPrune experts. having just reviewed the topic from start to finish the following reasons for the crash were. Engine failure and/ or both, water in hull, Torque set too low, throttle friction locks, and even control seat collapsed/went backwards. No one picked the rudder trim set right over. Dick Smith in a way came closest when in April stated this would never had happened if the pilot was grounded after he had an incident at Mt Hotham some time previous see post 716.( My guess Dick had some inside info on the investigation this time). So sadly it appears the pilot in question did not use a check list, never been in a sim and apparently stated he didn't need to. His carefree attitude finally caught up with him and sadly he took his passengers with him.
Lesson for all of us.

Some of the people he flew with said he did use a checklist, some said he didn't. It could not be determined if he used a checklist on this flight.